A variety of types of machines and processes exist for making folded sheet products such as paper hand towels, facial tissues, sheets of tin foil, and the like by producing stacks of interfolded sheets, or non-interfolded sheets, having a desired folded width.
In one form of a folded sheet, each sheet is folded only once to form double-panel sheets having two panels joined along a common fold line. It is desirable to interfold panels of successive sheets, at the same time as the sheets are being folded, by partially overlapping the individual sheets in the stack during the folding process. The overlapping and folding is carried out in such a manner that, with the interfolded stack loaded into a dispenser, when a sheet is pulled out of the dispenser at least one panel of the following sheet is also pulled out of the dispenser to facilitate pulling the next sheet from the dispenser.
The production of single-fold interfolded product has traditionally been performed with an interfolder that utilizes two separate webs from which two separate streams of sheets are formed. The streams of sheets are offset from one another such that the sheets from one stream overlap the sheets from the other stream by 50%. As such, each sheet overlaps two sheets from the other stream. Unfortunately, the use of two separate webs of material requires a significant duplication in components including two rolls of paper, two unwind stands, two web handling systems, two web embossers, two web cutoff systems, and two transfer paths for supplying the sheets to a single set of folding rolls that interfold the sheets.
The assignee of the instant application has also developed a system that will use only a single web material, but that passes sheets separated from the single web along two separate sheet flow paths to facilitate the proper orientation (see e.g. FIG. 3) of the sheets prior to passage through folding rolls of the system. Such a system is illustrated in U.S. patent application Ser. No. 12/977,393 entitled “Single Web Single-Fold Apparatus and Method,” to Tad Butterworth, filed on Dec. 23, 2010.
Unfortunately, both of these systems are complex, expensive, and generally large. The present invention provides an improved system that provides the proper overlap for a single-fold interfolded stream of sheets while using a simple, more compact system by passing all sheets substantially along a single sheet flow path.